Improvement in valves for compound steam-engines



2Sheets--Sheet-1. H. lFVAIRGHIEVE.

Improvement in Valvesfor Compound-Steam-En'gines.

No. 132,649. Patented ocr. 29,1872.

2 SheeS--Sheet 2.

-H. FAlRGRl-EVE.

- Y Improvement in Varfvesfor Compound Steam-Engines.

No. 132,649. Patented 061.291,1872. 1

STATES PATENT OFFICE. i

HUGH FAIRGRIEVE, OF HAMILTONGANADA.

- y f Y 7 IMPROVEMENT IN VALVES FOR COMPIOUND STEAM-ENGINES.

Speciication forming part of Letters Patent No. 132,649, dated October 29, 1872.

To all whom it may concern:

Be it known that I, HUGE; FAIEGRrEvE, of the city of Hamilton, county of Wentworth, Province of Ontario, Canada, have invented a new and useful Improvement in the Valves of Steam-Engines; and I do hereby decla-re 'pound or single-cylinder engines, as hereinafter described; second, from vthe small amount of unproductive expansion as well as from the non-exposure of the steam to condensing influences between the two cylinders as applied to compound steam-engines.

In the accompanying drawing similar letters of reference indicate corresponding parts.

Figure 1 is a sectional elevation of a portion of the two cylinders, marked N and O, with their respective pistons It and S; of the valve-chest B with the adjustable pressurevalves V and W and of the valve A, in which valve A there are two cavities, ff.

Y In the face of the large cylinder O, which is shown in section, there are rive ports, (four steam-ports and an exhaust-port.) The ports b b form a direct communication between the cylinders N and O, outside and independent of the valve-chest B. The steam-ports c c, by means of the cavities ff of the valve A, form a communication with the aforesaid ports b b, which releases the steam from the cylin` der N and admits it to the cylinder O. The cavities f f form, also, a communication between the ports c c and the exhaust-port d, which conducts the steam to the condenser of the engine. v

Fig. 2 is a front view of the valve A, showing the cavities f f. Fig. 3 is a front view admission-valves E E and the cut-off valves g g for regulating the admission of the steam from .the boiler to the high-pressure cylinder N, which are shown only in the drawing. (They forming no part of this invention, it was not considered necessary to show them in the model.)

This improved valve, as applied to comy Vpound steam-engines, works upon the face of the large or low-pressure cylinder O, Aand receives the steam from the high-pressure cylinder N under its face, through the ports b b, which are outside and independent of the valve-chest B; and, as applied to single-cylinder engines, it receives the steam direct from.

the boiler through the ports b b, without the intervention of the high-pressure cylinder N, the valve-chest B in both cases being used vsolely for the purpose of balancing the valve cylinder O to escape through the other port c into the exhaust-port d, which conducts it to the condenser of the engine.

I make no claim to a slide-valve, such asl the valve A, as adapted to be used in the ordinary steam-chest of any steam-engine where the steam must pass through the said chest in its passage to the cylinder or cylinders; but

What I do claim as my invention isl. The arrangement ofthe valve A adapted for operation in relation to the cylinders N and O, with the valve-chest B, as and for the purpose described.

2. The valve-chest B and the adjustable pressure-valves V and W, for the purpose of balancing the said valve A, in connection with` either compound or single cylinder engines, substantially as described, and for the purpose set forth.

Hamilton, March 9, 1872.

HUGH FAIRGRIEVE. Witnesses: J. B. FAIRGEIEVE,

WILLIAM GILL. 

